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Yuan S, Bremmer A, Yang X, Li J, Hu Q. Splittable systems in biomedical applications. Biomater Sci 2024; 12:4103-4116. [PMID: 39012216 DOI: 10.1039/d4bm00709c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Splittable systems have emerged as a powerful approach for the precise spatiotemporal control of biological processes. This concept relies on splitting a functional molecule into inactive fragments, which can be reassembled under specific conditions or stimuli to regain activity. Several binding pairs and orthogonal split fragments are introduced by fusing with other modalities to develop more complex and robust designs. One of the pillars of these splittable systems is modularity, which involves decoupling targeting, activation, and effector functions. Challenges, such as off-target effects and overactivation, can be addressed through precise control. This review provides an overview of the design principles, strategies, and applications of splittable systems across diverse fields including immunotherapy, gene editing, prodrug activation, biosensing, and synthetic biology.
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Affiliation(s)
- Sichen Yuan
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA.
- Wisconsin Center for NanoBioSystems, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA
- Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA
| | - Alexa Bremmer
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA.
| | - Xicheng Yang
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA.
| | - Jiayue Li
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA.
| | - Quanyin Hu
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA.
- Wisconsin Center for NanoBioSystems, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA
- Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin, Madison (UW-Madison), Madison, Wisconsin 53705, USA
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2
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Lehmann T, Schneider H, Tonillo J, Schanz J, Schwarz D, Schröter C, Jäger S, Kolmar H, Hecht S, Anderl J, Rasche N, Rieker M, Dickgiesser S. Welding PROxAb Shuttles: A Modular Approach for Generating Bispecific Antibodies via Site-Specific Protein-Protein Conjugation. Bioconjug Chem 2024; 35:780-789. [PMID: 38809610 DOI: 10.1021/acs.bioconjchem.4c00124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
Targeted protein degradation is an innovative therapeutic strategy to selectively eliminate disease-causing proteins. Exemplified by proteolysis-targeting chimeras (PROTACs), they have shown promise in overcoming drug resistance and targeting previously undruggable proteins. However, PROTACs face challenges, such as low oral bioavailability and limited selectivity. The recently published PROxAb Shuttle technology offers a solution enabling the targeted delivery of PROTACs using antibodies fused with PROTAC-binding domains derived from camelid single-domain antibodies (VHHs). Here, a modular approach to quickly generate PROxAb Shuttles by enzymatically coupling PROTAC-binding VHHs to off-the-shelf antibodies was developed. The resulting conjugates retained their target binding and internalization properties, and incubation with BRD4-targeting PROTACs resulted in formation of defined PROxAb-PROTAC complexes. These complexes selectively induced degradation of the BRD4 protein, resulting in cytotoxicity specifically to cells expressing the antibody's target. The chemoenzymatic approach described herein provides a versatile and efficient solution for generating antibody-VHH conjugates for targeted protein degradation applications, but it could also be used to combine antibodies and VHH binders to generate bispecific antibodies for further applications.
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Affiliation(s)
- Tanja Lehmann
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Hendrik Schneider
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Jason Tonillo
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Jennifer Schanz
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Daniel Schwarz
- Discovery Pharmacology, Merck KGaA, 64293 Darmstadt, Germany
| | | | - Sebastian Jäger
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Harald Kolmar
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Stefan Hecht
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Jan Anderl
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Nicolas Rasche
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
| | - Marcel Rieker
- ADCs & Targeted NBE Therapeutics, Merck KGaA, 64293 Darmstadt , Germany
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3
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Driscoll CL, Keeble AH, Howarth MR. SpyMask enables combinatorial assembly of bispecific binders. Nat Commun 2024; 15:2403. [PMID: 38493197 PMCID: PMC10944524 DOI: 10.1038/s41467-024-46599-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 03/04/2024] [Indexed: 03/18/2024] Open
Abstract
Bispecific antibodies are a successful and expanding therapeutic class. Standard approaches to generate bispecifics are complicated by the need for disulfide reduction/oxidation or specialized formats. Here we present SpyMask, a modular approach to bispecifics using SpyTag/SpyCatcher spontaneous amidation. Two SpyTag-fused antigen-binding modules can be precisely conjugated onto DoubleCatcher, a tandem SpyCatcher where the second SpyCatcher is protease-activatable. We engineer a panel of structurally-distinct DoubleCatchers, from which binders project in different directions. We establish a generalized methodology for one-pot assembly and purification of bispecifics in 96-well plates. A panel of binders recognizing different HER2 epitopes were coupled to DoubleCatcher, revealing unexpected combinations with anti-proliferative or pro-proliferative activity on HER2-addicted cancer cells. Bispecific activity depended sensitively on both binder orientation and DoubleCatcher scaffold geometry. These findings support the need for straightforward assembly in different formats. SpyMask provides a scalable tool to discover synergy in bispecific activity, through modulating receptor organization and geometry.
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Affiliation(s)
- Claudia L Driscoll
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1PD, UK
| | - Anthony H Keeble
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1PD, UK
| | - Mark R Howarth
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1PD, UK.
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4
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Barron N, Dickgiesser S, Fleischer M, Bachmann AN, Klewinghaus D, Hannewald J, Ciesielski E, Kusters I, Hammann T, Krause V, Fuchs SW, Siegmund V, Gross AW, Mueller-Pompalla D, Krah S, Zielonka S, Doerner A. A Generic Approach for Miniaturized Unbiased High-Throughput Screens of Bispecific Antibodies and Biparatopic Antibody-Drug Conjugates. Int J Mol Sci 2024; 25:2097. [PMID: 38396776 PMCID: PMC10889805 DOI: 10.3390/ijms25042097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/30/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024] Open
Abstract
The toolbox of modern antibody engineering allows the design of versatile novel functionalities exceeding nature's repertoire. Many bispecific antibodies comprise heterodimeric Fc portions recently validated through the approval of several bispecific biotherapeutics. While heterodimerization methodologies have been established for low-throughput large-scale production, few approaches exist to overcome the bottleneck of large combinatorial screening efforts that are essential for the identification of the best possible bispecific antibody. This report presents a novel, robust and miniaturized heterodimerization process based on controlled Fab-arm exchange (cFAE), which is applicable to a variety of heterodimeric formats and compatible with automated high-throughput screens. Proof of applicability was shown for two therapeutic molecule classes and two relevant functional screening read-outs. First, the miniaturized production of biparatopic anti-c-MET antibody-drug conjugates served as a proof of concept for their applicability in cytotoxic screenings on tumor cells with different target expression levels. Second, the automated workflow enabled a large unbiased combinatorial screening of biparatopic antibodies and the identification of hits mediating potent c-MET degradation. The presented workflow utilizes standard equipment and may serve as a facile, efficient and robust method for the discovery of innovative therapeutic agents in many laboratories worldwide.
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Affiliation(s)
- Nadine Barron
- Protein and Cell Sciences, EMD Serono, 45A Middlesex Turnpike, Billerica, MA 01821, USA
| | - Stephan Dickgiesser
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Markus Fleischer
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | | | - Daniel Klewinghaus
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Jens Hannewald
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Elke Ciesielski
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Ilja Kusters
- Protein Engineering and Antibody Technologies, EMD Serono, 45A Middlesex Turnpike, Billerica, MA 01821, USA
| | - Til Hammann
- Discovery Pharmacology, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Volker Krause
- Discovery Pharmacology, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | | | - Vanessa Siegmund
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Alec W. Gross
- Protein Engineering and Antibody Technologies, EMD Serono, 45A Middlesex Turnpike, Billerica, MA 01821, USA
| | - Dirk Mueller-Pompalla
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Simon Krah
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Stefan Zielonka
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
| | - Achim Doerner
- NBE Technologies, Merck Healthcare KGaA, Frankfurter Str. 250, 64293 Darmstadt, Germany
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5
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Madsen AV, Pedersen LE, Kristensen P, Goletz S. Design and engineering of bispecific antibodies: insights and practical considerations. Front Bioeng Biotechnol 2024; 12:1352014. [PMID: 38333084 PMCID: PMC10850309 DOI: 10.3389/fbioe.2024.1352014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/15/2024] [Indexed: 02/10/2024] Open
Abstract
Bispecific antibodies (bsAbs) have attracted significant attention due to their dual binding activity, which permits simultaneous targeting of antigens and synergistic binding effects beyond what can be obtained even with combinations of conventional monospecific antibodies. Despite the tremendous therapeutic potential, the design and construction of bsAbs are often hampered by practical issues arising from the increased structural complexity as compared to conventional monospecific antibodies. The issues are diverse in nature, spanning from decreased biophysical stability from fusion of exogenous antigen-binding domains to antibody chain mispairing leading to formation of antibody-related impurities that are very difficult to remove. The added complexity requires judicious design considerations as well as extensive molecular engineering to ensure formation of high quality bsAbs with the intended mode of action and favorable drug-like qualities. In this review, we highlight and summarize some of the key considerations in design of bsAbs as well as state-of-the-art engineering principles that can be applied in efficient construction of bsAbs with diverse molecular formats.
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Affiliation(s)
- Andreas V. Madsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Lasse E. Pedersen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Peter Kristensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Steffen Goletz
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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6
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Shepherd A, Bennychen B, Marcil A, Bloemberg D, Pon RA, Weeratna RD, McComb S. A simplified function-first method for the discovery and optimization of bispecific immune engaging antibodies. PLoS One 2023; 18:e0273884. [PMID: 37347762 PMCID: PMC10286961 DOI: 10.1371/journal.pone.0273884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 05/28/2023] [Indexed: 06/24/2023] Open
Abstract
Bi-specific T-cell engager antibodies (BiTEs) are synthetic fusion molecules that combine multiple antibody-binding domains to induce active contact between T-cells and antigen expressing cells in the body. Blinatumomab, a CD19-CD3 BiTE is now a widely used therapy for relapsed B-cell malignancies, and similar BiTE therapeutics have shown promise for treating various other forms of cancer. The current process for new BiTE development is time consuming and costly, requiring characterization of the individual antigen binding domains, followed by bi-specific design, protein production, purification, and eventually functional screening. Here, we sought to establish a more cost-efficient approach for generating novel BiTE sequences and assessing bioactivity through a function first approach without purification. We generate a plasmid with a bi-modular structure to allow high-throughput exchange of either binding arm, enabling rapid screening of novel tumour-targeting single chain variable (scFv) domains in combination with the well-characterized OKT3 scFv CD3-targeting domain. We also demonstrate two systems for high throughput functional screening of BiTE proteins based on Jurkat T cells (referred to as BiTE-J). Using BiTE-J we evaluate four EGFRvIII-scFv sequenced in BiTE format, identifying two constructs with superior activity for redirecting T-cells against the EGFRvIII-tumour specific antigen. We also confirm activity in primary T cells, where novel EGFRvIII-BiTEs induced T cell activation and antigen selective tumor killing. We finally demonstrate similar exchange the CD3-interacting element of our bi-modular plasmid. By testing several novel CD3-targeting scFv elements for activity in EGFRvIII-targeted BiTEs, we were able to identify highly active BiTE molecules with desirable functional activity for downstream development. In summary, BiTE-J presents a low cost, high-throughput method for the rapid assessment of novel BiTE molecules without the need for purification and quantification.
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Affiliation(s)
- Alex Shepherd
- Human Health Therapeutics Research Centre, National Research Council, Ottawa, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Bigitha Bennychen
- Human Health Therapeutics Research Centre, National Research Council, Ottawa, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
| | - Anne Marcil
- Human Health Therapeutics Research Centre, National Research Council, Ottawa, Canada
| | - Darin Bloemberg
- Human Health Therapeutics Research Centre, National Research Council, Ottawa, Canada
| | - Robert A. Pon
- Human Health Therapeutics Research Centre, National Research Council, Ottawa, Canada
| | - Risini D. Weeratna
- Human Health Therapeutics Research Centre, National Research Council, Ottawa, Canada
| | - Scott McComb
- Human Health Therapeutics Research Centre, National Research Council, Ottawa, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Canada
- Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, Canada
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7
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Koga H, Yamano T, Betancur J, Nagatomo S, Ikeda Y, Yamaguchi K, Nabuchi Y, Sato K, Teranishi-Ikawa Y, Sato M, Hirayama H, Hayasaka A, Torizawa T, Haraya K, Sampei Z, Shiraiwa H, Kitazawa T, Igawa T, Kuramochi T. Efficient production of bispecific antibody by FAST-Ig TM and its application to NXT007 for the treatment of hemophilia A. MAbs 2023; 15:2222441. [PMID: 37339067 DOI: 10.1080/19420862.2023.2222441] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/22/2023] Open
Abstract
Efficient production of bispecific antibodies (BsAbs) in single mammalian cells is essential for basic research and industrial manufacturing. However, preventing unwanted pairing of heavy chains (HCs) and light chains (LCs) is a challenging task. To address this, we created an engineering technology for preferential cognate HC/LC and HC/HC paring called FAST-Ig (Four-chain Assembly by electrostatic Steering Technology - Immunoglobulin), and applied it to NXT007, a BsAb for the treatment of hemophilia A. We introduced charged amino-acid substitutions at the HC/LC interface to facilitate the proper assembly for manufacturing a standard IgG-type BsAb. We generated CH1/CL interface-engineered antibody variants that achieved > 95% correct HC/LC pairing efficiency with favorable pharmacological properties and developability. Among these, we selected a design (C3) that allowed us to separate the mis-paired species with an unintended pharmacological profile using ion-exchange chromatography. Crystal structure analysis demonstrated that the C3 design did not affect the overall structure of both Fabs. To determine the final design for HCs-heterodimerization, we compared the stability of charge-based and knobs into hole-based Fc formats in acidic conditions and selected the more stable charge-based format. FAST-Ig was also applicable to stable CHO cell lines for industrial production and demonstrated robust chain pairing with different subclasses of parent BsAbs. Thus, it can be applied to a wide variety of BsAbs both preclinically and clinically.
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Affiliation(s)
- Hikaru Koga
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Takashi Yamano
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Juan Betancur
- API Process Development Department, Chugai Pharmaceutical Co., Ltd, Ukima, Tokyo, Japan
| | - Satoko Nagatomo
- Analytical Development Department, Chugai Pharmaceutical Co, Ltd, Ukima, Tokyo, Japan
| | - Yousuke Ikeda
- Analytical Development Department, Chugai Pharmaceutical Co, Ltd, Ukima, Tokyo, Japan
| | - Kazuki Yamaguchi
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Yoshiaki Nabuchi
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Kazuki Sato
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | | | - Motohiko Sato
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Hiroyuki Hirayama
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Akira Hayasaka
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Takuya Torizawa
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Kenta Haraya
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Zenjiro Sampei
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Hirotake Shiraiwa
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Takehisa Kitazawa
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
| | - Tomoyuki Igawa
- Translational Research Division, Chugai Pharmaceutical Co., Ltd, Chuo-Ku, Tokyo, Japan
| | - Taichi Kuramochi
- Research Division, Chugai Pharmaceutical Co., Ltd, Yokohama, Kanagawa, Japan
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8
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Abstract
Not required for editorial.
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Affiliation(s)
- Nimish Gera
- Mythic Therapeutics Inc., 100 Beaver Street, Waltham, MA 02453 USA
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9
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Zong H, Han L, Chen J, Pan Z, Wang L, Sun R, Ding K, Xie Y, Jiang H, Lu H, Gilly J, Zhang B, Zhu J. Kinetics study of the natural split Npu DnaE intein in the generation of bispecific IgG antibodies. Appl Microbiol Biotechnol 2021; 106:161-171. [PMID: 34882254 DOI: 10.1007/s00253-021-11707-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/17/2021] [Accepted: 11/20/2021] [Indexed: 10/19/2022]
Abstract
Rapid and efficient bispecific antibody (BsAb) production for industrial applications is still facing many challenges. We reported a technology platform for generating bispecific IgG antibodies, "Bispecific Antibody by Protein Trans-splicing (BAPTS)." While the "BAPTS" method has shown potential in high-throughput screening of BsAbs, further understanding and optimizing the methodology is desirable. A large number of BsAbs were selected to illustrate the conversion efficiency and kinetics parameters. The temperature of reaction makes no significant influence in conversion efficiency, which can reach more than 70% within 2 h, and CD3 × HER2 BsAb can reach 90%. By fitting trans-splicing reaction to single-component exponential decay curves, the apparent first-order rate constants at a series of temperatures were determined. The rate constant ranges from 0.02 to 0.11 min-1 at 37 °C, which is a high rate reported for the protein trans-splicing reaction (PTS). The reaction process is activated rapidly with activation energy of 8.9 kcal·mol-1 (CD3 × HER2) and 5.2 kcal·mol-1 (CD3 × EGFR). The BsAbs generated by "BAPTS" technology not only had the similar post-translation modifications to the parental antibodies, but also demonstrated excellent in vitro and in vivo bioactivity. The kinetics parameters and activation energy of the reaction illustrate feasible for high-throughput screening and industrial applications using the "BAPTS" approach. KEY POINTS: • The trans-splicing reaction of Npu DnaE intein in "BAPTS" platform is a rapid process with low reaction activation and high rate. • The BsAb generated by "BAPTS" remained effective in tumor cell killing. • The kinetics parameters and activation energy of the reaction illustrate feasible for high-throughput screening and industrial applications using the "BAPTS" approach.
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Affiliation(s)
- Huifang Zong
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Lei Han
- Jecho Biopharmaceuticals Co., Ltd., Tianjin, China
| | - Jie Chen
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Zhidi Pan
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Lei Wang
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Rui Sun
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Kai Ding
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Yueqing Xie
- Jecho Laboratories, Inc., Frederick, MD, USA
| | - Hua Jiang
- Jecho Biopharmaceuticals Co., Ltd., Tianjin, China.,Jecho Laboratories, Inc., Frederick, MD, USA
| | - Huili Lu
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - John Gilly
- Jecho Biopharmaceuticals Co., Ltd., Tianjin, China
| | - Baohong Zhang
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China.
| | - Jianwei Zhu
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China. .,Jecho Biopharmaceuticals Co., Ltd., Tianjin, China. .,Jecho Laboratories, Inc., Frederick, MD, USA.
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10
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Production of IgG1-based bispecific antibody without extra cysteine residue via intein-mediated protein trans-splicing. Sci Rep 2021; 11:19411. [PMID: 34593913 PMCID: PMC8484483 DOI: 10.1038/s41598-021-98855-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 09/09/2021] [Indexed: 11/09/2022] Open
Abstract
A major class of bispecific antibodies (BsAbs) utilizes heterodimeric Fc to produce the native immunoglobulin G (IgG) structure. Because appropriate pairing of heavy and light chains is required, the design of BsAbs produced through recombination or reassembly of two separately-expressed antigen-binding fragments is advantageous. One such method uses intein-mediated protein trans-splicing (IMPTS) to produce an IgG1-based structure. An extra Cys residue is incorporated as a consensus sequence for IMPTS in successful examples, but this may lead to potential destabilization or disturbance of the assay system. In this study, we designed a BsAb linked by IMPTS, without the extra Cys residue. A BsAb binding to both TNFR2 and CD30 was successfully produced. Cleaved side product formation was inevitable, but it was minimized under the optimized conditions. The fine-tuned design is suitable for the production of IgG-like BsAb with high symmetry between the two antigen-binding fragments that is advantageous for screening BsAbs.
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11
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Sun R, Zhou Y, Han L, Pan Z, Chen J, Zong H, Bian Y, Jiang H, Zhang B, Zhu J. A Rational Designed Novel Bispecific Antibody for the Treatment of GBM. Biomedicines 2021; 9:biomedicines9060640. [PMID: 34204931 PMCID: PMC8230177 DOI: 10.3390/biomedicines9060640] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/26/2021] [Accepted: 05/28/2021] [Indexed: 01/02/2023] Open
Abstract
Epidermal growth factor receptor variant III (EGFRvIII) is highly and specifically expressed in a subset of lethal glioblastoma (GBM), making the receptor a unique therapeutic target for GBM. Recently, bispecific antibodies (BsAbs) have shown exciting clinical benefits in cancer immunotherapy. Here, we report remarkable results for GBM treatment with a BsAb constructed by the "BAPTS" method. The BsAb was characterized through LC/MS, SEC-HPLC, and SPR. Furthermore, the BsAb was evaluated in vitro for bioactivities through FACS, antigen-dependent T-cell-mediated cytotoxicity, and a cytokine secretion assay, as well as in vivo for antitumor activity and pharmacokinetic (PK) parameters through immunodeficient NOD/SCID and BALB/c mouse models. The results indicated that the EGFRvIII-BsAb eliminated EGFRvIII-positive GBM cells by recruiting and stimulating effector T cells secreting cytotoxic cytokines that killed GBM cells in vitro. The results demonstrated the antitumor potential and long circulation time of EGFRvIII-BsAb in NOD/SCID mice bearing de2-7 subcutaneously heterotopic transplantation tumors and BALB/c mice. In conclusion, our experiments in both in vitro and in vivo have shown the remarkable antitumor activities of EGFRvIII-BsAb, highlighting its potential in clinical applications for the treatment of GBM. Additional merits, including a long circulation time and low immunogenicity, have also made the novel BsAb a promising therapeutic candidate.
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Affiliation(s)
- Rui Sun
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
| | - Yuexian Zhou
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
| | - Lei Han
- Jecho Biopharmaceuticals Co., Ltd. No. 2018 Zhongtian Avenue, Binhai New Area, Tianjin 300457, China; (L.H.); (H.J.)
- Jecho Biopharmaceutical Institute, No. 58 Yuanmei Road, Minhang District, Shanghai 200241, China
| | - Zhidi Pan
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
| | - Jie Chen
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
| | - Huifang Zong
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
| | - Yanlin Bian
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
| | - Hua Jiang
- Jecho Biopharmaceuticals Co., Ltd. No. 2018 Zhongtian Avenue, Binhai New Area, Tianjin 300457, China; (L.H.); (H.J.)
- Jecho Laboratories Inc., 7320 Executive Way, Frederick, MD 21704, USA
| | - Baohong Zhang
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
- Correspondence: (B.Z.); (J.Z.)
| | - Jianwei Zhu
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240, China; (R.S.); (Y.Z.); (Z.P.); (J.C.); (H.Z.); (Y.B.)
- Jecho Laboratories Inc., 7320 Executive Way, Frederick, MD 21704, USA
- Correspondence: (B.Z.); (J.Z.)
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12
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Hentrich C, Kellmann SJ, Putyrski M, Cavada M, Hanuschka H, Knappik A, Ylera F. Periplasmic expression of SpyTagged antibody fragments enables rapid modular antibody assembly. Cell Chem Biol 2021; 28:813-824.e6. [PMID: 33529581 DOI: 10.1016/j.chembiol.2021.01.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/16/2020] [Accepted: 01/06/2021] [Indexed: 12/15/2022]
Abstract
Antibodies are essential tools in research and diagnostics. Although antibody fragments typically obtained from in vitro selection can be rapidly produced in bacteria, the generation of full-length antibodies or the modification of antibodies with probes is time and labor intensive. Protein ligation such as SpyTag technology could covalently attach domains and labels to antibody fragments equipped with a SpyTag. However, we found that the established periplasmic expression of antibody fragments in E. coli led to quantitative cleavage of the SpyTag by the proteases Tsp and OmpT. Here we report successful periplasmic expression of SpyTagged Fab fragments and demonstrate the coupling to separately prepared SpyCatcher modules. We used this modular toolbox of SpyCatcher proteins to generate reagents for a variety of immunoassays and measured their performance in comparison with traditional reagents. Furthermore, we demonstrate surface immobilization, high-throughput screening of antibody libraries, and rapid prototyping of antibodies based on modular antibody assembly.
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Affiliation(s)
| | | | - Mateusz Putyrski
- Bio-Rad AbD Serotec GmbH, Zeppelinstraße 4, 82178 Puchheim, Germany
| | - Manuel Cavada
- Bio-Rad AbD Serotec GmbH, Zeppelinstraße 4, 82178 Puchheim, Germany
| | - Hanh Hanuschka
- Bio-Rad AbD Serotec GmbH, Zeppelinstraße 4, 82178 Puchheim, Germany
| | - Achim Knappik
- Bio-Rad AbD Serotec GmbH, Zeppelinstraße 4, 82178 Puchheim, Germany
| | - Francisco Ylera
- Bio-Rad AbD Serotec GmbH, Zeppelinstraße 4, 82178 Puchheim, Germany.
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13
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Bhatta P, Whale KD, Sawtell AK, Thompson CL, Rapecki SE, Cook DA, Twomey BM, Mennecozzi M, Starkie LE, Barry EMC, Peters SJ, Kamal AM, Finney HM. Bispecific antibody target pair discovery by high-throughput phenotypic screening using in vitro combinatorial Fab libraries. MAbs 2021; 13:1859049. [PMID: 33487120 PMCID: PMC7849716 DOI: 10.1080/19420862.2020.1859049] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Bispecific antibodies can uniquely influence cellular responses, but selecting target combinations for optimal functional activity remains challenging. Here we describe a high-throughput, combinatorial, phenotypic screening approach using a new bispecific antibody target discovery format, allowing screening of hundreds of target combinations. Simple in vitro mixing of Fab-fusion proteins from a diverse library enables the generation of thousands of screen-ready bispecific antibodies for high-throughput, biologically relevant assays. We identified an obligate bispecific co-targeting CD79a/b and CD22 as a potent inhibitor of human B cell activation from a short-term flow cytometry signaling assay. A long-term, high-content imaging assay identified anti-integrin bispecific inhibitors of human cell matrix accumulation targeting integrins β1 and β6 or αV and β1. In all cases, functional activity was conserved from the bispecific screening format to a therapeutically relevant format. We also introduce a broader type of mechanistic screen whereby functional modulation of different cell subsets in peripheral blood mononuclear cells was evaluated simultaneously. We identified bispecific antibodies capable of activating different T cell subsets of potential interest for applications in oncology or infectious disease, as well as bispecifics abrogating T cell activity of potential interest to autoimmune or inflammatory disease. The bispecific target pair discovery technology described herein offers access to new target biology and unique bispecific therapeutic opportunities in diverse disease indications.
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Affiliation(s)
- Pallavi Bhatta
- New Modalities and Therapeutics Group, UCB Pharma, Slough , Berkshire UK
| | - Kevin D Whale
- In Vitro Pharmacology Group, UCB Pharma, Slough , Berkshire, UK
| | - Amy K Sawtell
- In Vitro Pharmacology Group, UCB Pharma, Slough , Berkshire, UK
| | | | - Stephen E Rapecki
- New Modalities and Therapeutics Group, UCB Pharma, Slough , Berkshire UK
| | - David A Cook
- In Vitro Pharmacology Group, UCB Pharma, Slough , Berkshire, UK
| | - Breda M Twomey
- In Vitro Pharmacology Group, UCB Pharma, Slough , Berkshire, UK
| | | | - Laura E Starkie
- New Modalities and Therapeutics Group, UCB Pharma, Slough , Berkshire UK
| | - Emily M C Barry
- New Modalities and Therapeutics Group, UCB Pharma, Slough , Berkshire UK
| | - Shirley J Peters
- New Modalities and Therapeutics Group, UCB Pharma, Slough , Berkshire UK
| | - Ahmad M Kamal
- Immunology Partnering Group, UCB Pharma , Slough, Berkshire UK
| | - Helene M Finney
- In Vitro Pharmacology Group, UCB Pharma, Slough , Berkshire, UK
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14
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Park J, Lee S, Kim Y, Yoo TH. Methods to generate site-specific conjugates of antibody and protein. Bioorg Med Chem 2021; 30:115946. [DOI: 10.1016/j.bmc.2020.115946] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/07/2020] [Accepted: 12/09/2020] [Indexed: 02/07/2023]
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15
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Sawant MS, Streu CN, Wu L, Tessier PM. Toward Drug-Like Multispecific Antibodies by Design. Int J Mol Sci 2020; 21:E7496. [PMID: 33053650 PMCID: PMC7589779 DOI: 10.3390/ijms21207496] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/02/2020] [Accepted: 10/02/2020] [Indexed: 12/18/2022] Open
Abstract
The success of antibody therapeutics is strongly influenced by their multifunctional nature that couples antigen recognition mediated by their variable regions with effector functions and half-life extension mediated by a subset of their constant regions. Nevertheless, the monospecific IgG format is not optimal for many therapeutic applications, and this has led to the design of a vast number of unique multispecific antibody formats that enable targeting of multiple antigens or multiple epitopes on the same antigen. Despite the diversity of these formats, a common challenge in generating multispecific antibodies is that they display suboptimal physical and chemical properties relative to conventional IgGs and are more difficult to develop into therapeutics. Here we review advances in the design and engineering of multispecific antibodies with drug-like properties, including favorable stability, solubility, viscosity, specificity and pharmacokinetic properties. We also highlight emerging experimental and computational methods for improving the next generation of multispecific antibodies, as well as their constituent antibody fragments, with natural IgG-like properties. Finally, we identify several outstanding challenges that need to be addressed to increase the success of multispecific antibodies in the clinic.
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Affiliation(s)
- Manali S. Sawant
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI 48109, USA; (M.S.S.); (C.N.S.)
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA;
| | - Craig N. Streu
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI 48109, USA; (M.S.S.); (C.N.S.)
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA;
- Department of Chemistry, Albion College, Albion, MI 49224, USA
| | - Lina Wu
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA;
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Peter M. Tessier
- Department of Pharmaceutical Sciences, University of Michigan, Ann Arbor, MI 48109, USA; (M.S.S.); (C.N.S.)
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA;
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
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16
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Hofmann T, Krah S, Sellmann C, Zielonka S, Doerner A. Greatest Hits-Innovative Technologies for High Throughput Identification of Bispecific Antibodies. Int J Mol Sci 2020; 21:E6551. [PMID: 32911608 PMCID: PMC7554978 DOI: 10.3390/ijms21186551] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 09/03/2020] [Accepted: 09/04/2020] [Indexed: 12/15/2022] Open
Abstract
Recent years have shown a tremendous increase and diversification in antibody-based therapeutics with advances in production techniques and formats. The plethora of currently investigated bi- to multi-specific antibody architectures can be harnessed to elicit a broad variety of specific modes of actions in oncology and immunology, spanning from enhanced selectivity to effector cell recruitment, all of which cannot be addressed by monospecific antibodies. Despite continuously growing efforts and methodologies, the identification of an optimal bispecific antibody as the best possible combination of two parental monospecific binders, however, remains challenging, due to tedious cloning and production, often resulting in undesired extended development times and increased expenses. Although automated high throughput screening approaches have matured for pharmaceutical small molecule development, it was only recently that protein bioconjugation technologies have been developed for the facile generation of bispecific antibodies in a 'plug and play' manner. In this review, we provide an overview of the most relevant methodologies for bispecific screening purposes-the DuoBody concept, paired light chain single cell production approaches, Sortase A and Transglutaminase, the SpyTag/SpyCatcher system, and inteins-and elaborate on the benefits as well as drawbacks of the different technologies.
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Affiliation(s)
- Tim Hofmann
- Advanced Cell Culture Technologies, Merck Life Sciences KGaA, Frankfurter Strasse 250, D-64293 Darmstadt, Germany;
| | - Simon Krah
- Protein Engineering and Antibody Technologies, Merck Healthcare KGaA, Frankfurter Strasse 250, D-64293 Darmstadt, Germany; (S.K.); (C.S.); (S.Z.)
| | - Carolin Sellmann
- Protein Engineering and Antibody Technologies, Merck Healthcare KGaA, Frankfurter Strasse 250, D-64293 Darmstadt, Germany; (S.K.); (C.S.); (S.Z.)
| | - Stefan Zielonka
- Protein Engineering and Antibody Technologies, Merck Healthcare KGaA, Frankfurter Strasse 250, D-64293 Darmstadt, Germany; (S.K.); (C.S.); (S.Z.)
| | - Achim Doerner
- Protein Engineering and Antibody Technologies, Merck Healthcare KGaA, Frankfurter Strasse 250, D-64293 Darmstadt, Germany; (S.K.); (C.S.); (S.Z.)
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17
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Jaakkonen A, Volkmann G, Iwaï H. An off-the-Shelf Approach for the Production of Fc Fusion Proteins by Protein Trans-Splicing towards Generating a Lectibody In Vitro. Int J Mol Sci 2020; 21:ijms21114011. [PMID: 32503354 PMCID: PMC7313076 DOI: 10.3390/ijms21114011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 05/29/2020] [Accepted: 05/31/2020] [Indexed: 12/19/2022] Open
Abstract
Monoclonal antibodies, engineered antibodies, and antibody fragments have become important biological therapeutic platforms. The IgG format with bivalent binding sites has a modular structure with different biological roles, i.e., effector and binding functions, in different domains. We demonstrated the reconstruction of an IgG-like domain structure in vitro by protein ligation using protein trans-splicing. We produced various binding domains to replace the binding domain of IgG from Escherichia coli and the Fc domain of human IgG from Brevibacillus choshinensis as split-intein fusions. We showed that in vitro protein ligation could produce various Fc-fusions at the N-terminus in vitro from the independently produced domains from different organisms. We thus propose an off-the-shelf approach for the combinatorial production of Fc fusions in vitro with several distinct binding domains, particularly from naturally occurring binding domains. Antiviral lectins from algae are known to inhibit virus entry of HIV and SARS coronavirus. We demonstrated that a lectin could be fused with the Fc-domain in vitro by protein ligation, producing an IgG-like molecule as a “lectibody”. Such an Fc-fusion could be produced in vitro by this approach, which could be an attractive method for developing potential therapeutic agents against rapidly emerging infectious diseases like SARS coronavirus without any genetic fusion and expression optimization.
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Affiliation(s)
- Anniina Jaakkonen
- Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland; (A.J.); (G.V.)
- Present Address: Microbiology Unit, Finnish Food Authority, FI-00790 Helsinki, Finland
| | - Gerrit Volkmann
- Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland; (A.J.); (G.V.)
| | - Hideo Iwaï
- Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland; (A.J.); (G.V.)
- Correspondence: ; Tel.: +358-2941-59752
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